The brains, preserved in jars of formaldehyde, might include one believed to be that of clock tower sniper Charles Whitman. Whitman's 1966 rampage at the University of Texas killed 16 people, including his mother and wife.

Officials say that it's not yet clear if this was theft or a harmless prank.

"We think somebody may have taken the brains, but we don't know at all for sure," psychology Professor Tim Schallert, co-curator of the collection, told the Austin American-Statesman.

His co-curator, psychology Professor Lawrence Cormack, said, "It's entirely possible word got around among undergraduates and people started swiping them for living rooms or Halloween pranks."

The university said in a statement that it will investigate "the circumstances surrounding this collection since it came here nearly 30 years ago" and that it's "committed to treating the brain specimens with respect."

The university's agreement with the hospital required the school to remove any data that might identify the person from whom the brain came.